Technical Abstract:
Tetracycline (TC) is a significant class of antimicrobial agents in human and veterinary medicine. As a result of its extensive use, its residue level in foods of animal origin, its occurrence, distribution, and fate in the environment and its impact on the biosphere are of major concern. Field deployable instrumentation and methodologies are much needed for these diversified analytical tasks. A TC-specific analyzer was developed based on europium-sensitized luminescence and applied to food, aquacultural and environmental analyses. A protocol was developed to screen oxytetracycline (OTC) in trout muscle at 2 ppm, the FDA tolerance level. Centrifugation, filtration, and usage of acids and organic solvents are eliminated by extraction with small C18 sorbent strips. To monitor OTC in aquacultural marine systems, a 0-2 ppm linear dynamic range (LDR) (r2 = 0.994) was achieved with a 0.27-ppb limit of detection without enrichment. For OTC analysis in environmental waters, one to three orders-of-magnitude improvement in sensitivity was achieved using 3M Empore C18 disks for enrichment. These methods are simple, rapid, and low-cost, providing needed sensitivity, selectivity and throughput for field analyses.